An opioid-mediated polycystic ovary in Wistar rats

Background: Polycystic ovary syndrome (PCOS) is a common endocrine disorder that affects 6-10 percent of women in fertility age. The development mechanism of PCOS has been widely studied in laboratory animals. However, the role of the opioid system on ventro-medial hypothalamus is still not clear. The aim of present study was to investigate the effect of morphine in this part on the ovary of Wistar rats.Methods: Female Wistar rats, weighing 220-250g (in the diestrus phase) were cannulated under anesthetic by a stereotaxic device in the ventromedial hypothalamus (VMH) and spent a period of recovery. Afterwards, they were divided into four groups. The control group only received 1 μL of saline into their VMH. The group which was treated by morphine microinjection only received 0.1 to 0.4 μg of this opioid substance. The two remaining groups were treated by naloxone microinjection, and morphine injection preceded by naloxone pre-injection, respectively, in order to investigate the mediating role of opioid receptors. Three days later, the rats were killed and biopsies of ovaries were prepared for incision and staining. The results were analyzed by ANOVA test. Further analysis of the differences between the groups was conducted by means of Tukey s HSD post-hoc. pResult: According to the findings, receiving morphine into VMH led to developing PCOS (pConclusion: As the competing antagonist of morphine, naloxone prevented the effect of morphine on the axis of HPG. This would make possible an opioid mediation in the occurrence of the symptoms of PCOS.

کلیدواژه ها:

Female rat ، Naloxone ، Polycystic ovary syndrome ، Ventro-medial hypothalamus ، Morphine